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UNDER THE MICROSCOPE

You probably know this, but teeth are actually the first step in the digestion process. Chewing your food makes it much easier to break down once it gets into your stomach.

What you may not know is that teeth also help you speak clearly. Without them, you wouldn't be able to make many of the sounds you rely on to communicate. Just imagine trying to say, "I think these teeth are terrific" without your pearly whites to help.

What is a cavity and how do you get one?

Believe it or not, your mouth is teeming with bacteria all the time. It's completely normal — in fact, some bacteria is actually helpful by defending us from harmful germs. Regular brushing helps to keep these bacteria in check — 1,000 to 100,000 per tooth is considered to be a healthy range. But, there are some bad kinds of bacteria that attach themselves to teeth, multiply in numbers and grow into a colony. As time goes on, more bacteria of all different kinds and proteins from your saliva attach to that colony and become a whitish film on your teeth. This is known as plaque. The bacteria use the foods you eat (particularly those sugary snacks) as food and produce acid that eats away at the minerals that make up your enamel and form tiny holes in your tooth. These tiny holes grow into one big one — this is a cavity.

You can get a cavity by not keeping your teeth clean or by eating too many sugary foods.

What are wisdom teeth?

Wisdom teeth are molars that grow in at the very back of the mouth. They usually don't start growing until after the age of 16 and can crowd the other teeth in your mouth. For that reason, most people have their wisdom teeth removed. You can have just one wisdom tooth, or all four can come in. Getting them removed usually involves surgery at your dentist's office.

What exactly is enamel and why is it important for teeth?

Enamel is the hard covering over your teeth. It's made from mineral salts like calcium. It actually gets these minerals from your saliva, which helps make your enamel harder. It is these minerals though that can be attacked by acids.

What is the difference between baby teeth and permanent teeth?

Baby teeth are the first set of teeth that people develop during infancy. People usually have their complete set of baby teeth by the time they are three. At about seven, baby teeth come out. In their place, harder, larger teeth grow. These are the teeth that people have until they are adults and are known as permanent teeth.

What is fluoride and why does it help teeth become stronger?

Fluoride is a natural element that can be found in food and water. Scientists noticed that kids who lived in places where water had lots of fluoride already in it had fewer cavities. In fact, people who drink fluoridated water have 50 percent less tooth decay.

Once your body has soaked up fluoride, it is used by the cells that build your teeth to make your enamel harder and more resistant to plaque. Because of this, many states add fluoride to their drinking water.

Dentists also put fluoride treatments directly on your teeth when you get your teeth cleaned. This helps make your teeth much harder and more resistant to the acids that break down your enamel and cause cavities.